The present disclosure relates generally to railway cars and related components, and more particularly to a valve interlock system for a railway car.
The transportation industry transports a variety of products, including hazardous products, in many different types of transportation vehicles. For example, fuel, gas, and/or other hazardous chemicals are contained in tanker vehicles such as over-the-road trucks and railcars. Products contained in railcars including tanker cars may be released from the railcars using outlet valves including, for example, outlet ball valves. Known outlet valves may be operated using a valve operator configured to rotate the valve to an open or closed position. The outlet valve is normally in flow communication with discharge piping that transports the products from the railcar. When the railcar enters a receiving depot, the discharge piping is connected to receiving piping which can receive products contained in railway cars and transport such products to receptacles. As outlet valves are rotated between an open and/or a closed position using a valve operator, the outlet valves may be able to release products to, for example, the discharge piping. In alternative situations, the outlet valves may be able to release products to the ground underneath the railcar. Known products contained within railcars, including tanker cars, may be undesirable to release unintentionally. As a result, when valves including outlet valves are rotated to a partially or fully open position, products may drop from a railcar unintentionally while the railcar is stationary or in motion. If a valve operator is connected to the valve, the valve may be opened by outside forces. For example, extended and/or high vibrations and jarring events such as coupling and uncoupling of cars may cause the valve to be opened by a valve operator and accordingly such an opening of the valve may cause products to be released. Additionally, when a railcar has released a majority of its product from the tanker, it may still contain at least some residue. Accordingly, an open or partially open valve may result in residual product dropping from a railcar that is substantially emptied. In at least some cases, remediation related to the released product may be required.
Accordingly, a method of controlling the release of products, and more specifically, preventing outlet valves from remaining unintentionally partially or fully open is desirable when the valve operator has been disengaged. Specifically, a valve interlock system is needed such that the valve interlock prevents a valve operator from being removed from the outlet valve assembly while the outlet valve is in a partially or fully opened state.